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A satellite view of aerosols in the climate system

Nature volume 419, pages 215–223 (2002)Cite this article

Abstract

Anthropogenic aerosols are intricately linked to the climate system and to the hydrologic cycle. The net effect of aerosols is to cool the climate system by reflecting sunlight. Depending on their composition, aerosols can also absorb sunlight in the atmosphere, further cooling the surface but warming the atmosphere in the process. These effects of aerosols on the temperature profile, along with the role of aerosols as cloud condensation nuclei, impact the hydrologic cycle, through changes in cloud cover, cloud properties and precipitation. Unravelling these feedbacks is particularly difficult because aerosols take a multitude of shapes and forms, ranging from desert dust to urban pollution, and because aerosol concentrations vary strongly over time and space. To accurately study aerosol distribution and composition therefore requires continuous observations from satellites, networks of ground-based instruments and dedicated field experiments. Increases in aerosol concentration and changes in their composition, driven by industrialization and an expanding population, may adversely affect the Earth's climate and water supply.

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Figure 1: Global distribution of fine and coarse aerosol optical thickness (AOT) derived from MODIS measurements on the NASA Terra spacecraft for September 2000.
Figure 2: Model results of Chin et al.23 that correspond to the MODIS data of September 2000.
Figure 3: Satellite data and model calculations for a dust episode in east Asia advected over a pollution layer on 20 March 2001.
Figure 4: Comparison between concentration of anthropogenic aerosol and population density.
Figure 5: Solar radiative perturbation at the top of the atmosphere and the surface for the tropical Atlantic and Indian Ocean.
Figure 6: Schematic diagram of cloud formation in a clean and polluted atmosphere.
Figure 7: Effect of aerosol on cloud droplet and reflectance derived from POLDER and AVHRR spaceborne measurements.

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Acknowledgements

We thank F. M. Bréon, M. Chin, O. Dubovik, G. Feingold, P. Formenti, M. Herman, D. Herring, B. N. Holben, S. Mattoo, L. Remer and D. Rosenfeld for measurements and calculations used in this paper and for editorial comments. POLDER was a CNES/NASDA project; TOMS and MODIS are NASA projects.

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  1. NASA/Goddard Space Flight Center, Greenbelt, 20771, Maryland, USA

    Yoram J. Kaufman

  2. Laboratoire d'Optique Atmosphérique, Université de Lille/CNRS, Villeneuve d'Ascq, France

    Didier Tanré & Olivier Boucher

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Kaufman, Y., Tanré, D. & Boucher, O. A satellite view of aerosols in the climate system. Nature 419, 215–223 (2002). https://doi.org/10.1038/nature01091

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